Quoted:
I used a LNL case length gauge to check some once-fired cases; cases averaged 1.459. I sized the cases to 1.456, and they seem to load/fire fine.
I recently got a Wilson case gauge, and all of these cases are protruding above the max length of the gauge. I checked some other commercial ammo on hand, and they are all running 1.452-1.453 and are all in spec. It seems that 1.454 is max for this gauge.
But I've been following the advice I've seen here and elsewhere to go .003 or .004 smaller than chamber size.
So my question is this: is the gauge wrong, or is what I am doing wrong?
Every chamber is different. The Wilson (Or any other brand) Case Gauge is made to SAMMI Spec. SAMMI spec is such that it will chamber in ALL .223 chambers. If you are ONLY using your ammo in YOUR 1 rifle, than you are correct. Measure ~10 1x fired cases (Make sure you fire new ammo), then set your FL die to bump your headspace back 0.002"-0.004" from your average of the 10 cases.
The amount of headspace bump back is up to you, obviously the LESS you bump it back the less it is going to strech which should make it last longer, however you will likely get a split neck before you get case head seperation anyway. I personally use 0.003 bump back because if you size 100 cases you will notice it's virtually impossible to get every one the exact same, there's just too many variables, the best you could hope for is a +/- 0.001" variation. That would mean if your average bump back on 100 cases is 0.003" and you have a 0.001" variation, you would never bump back more than 0.004" and never less than 0.002". That's my theory..
Quoted:
Sorry, wasn't specific enough. Length to case shoulder as measured with LNL gauge.
As a side note, I did notice that the fired cases out of my nearly-new LMT carbine are running 1.463 (I spoke to them because it seemed excessive - they said it was okay and that they were using a Clymer Reamer)...does this sound kosher?
I have no idea what that means, but what is important is Do you plan on using your reloads in BOTH rifles? If you do, than things change a bit. You would need to measure 10 1x fired cases from BOTH rifles take the SMALLEST measurement, and bump back the sholder 0.002"-0.004" from there.
If your not soo much worried about trying to squeeze the few extra reloads out of your brass you can always just bump back to SAMMI specs and know it will chamber in EVERY rifle.
HTH
-Masta